Valves are known in diverse forms which are insufficiently suitable for introducing a medium into a container, particularly, if the container is filled with a material and is to meet superior hygienic requirements. The penetration of the container charge into indentations and gaps, which are characteristic of conventional valves, presents a special problem.
It is therefore an object of the invention to provide a valve which permits an efficient and economical introduction of the medium into a container, also with respect to the cleaning expenditures for the container if this container has to meet heightened hygienic demands.
This and other objects and advantages are achieved by a valve according to the invention, where the face of the valve needle, when the valve is closed, as well as the valve housing end essentially flush with an inner surface of the container.
In an embodiment, the valve face is mounted essentially in a plane with an outer surface of the container or at a small distance from this plane. This embodiment of the invention also has constructive advantages.
In another embodiment, when the valve is open, the valve needle is preferably overhung. Particularly preferably, a duct is provided for feeding the medium into the interior of the valve, whose longitudinal axis is arranged at an angle of between 30 and 90 degrees with respect to the longitudinal axis of the valve needle. The medium to be introduced therefore flows laterally onto the valve needle.
In still another embodiment, fits with low tolerance ranges are expediently provided between the container and the valve housing and/or between the valve housing and the valve needle.
In yet another embodiment, another object of the invention is the use of a valve constructed so that when the valve is closed, the face of the valve needle, as well as the valve housing, are essentially flush with an inner surface of the container. It is particularly advantageous to provide such a valve for introducing a cryogenic medium into a container, particularly a container containing food products.
When a valve according to an embodiment of the invention is installed, the surface of the interior wall of the container remains almost unchanged and smooth. This is particularly advantageous for containers which hold food products and which have to be cleaned on a regular basis. The risk of a bacteriological contamination by food residues, which are not picked up during the cleaning, can thereby be effectively lowered.
When closing a valve according to an embodiment of the invention, the valve is freed of any material which may have penetrated into the opened valve from the interior of the container. It is a special advantage that the valve is preferably inserted such that it closes in the direction of the material in the container. This is advantageous, for example, for highly viscous food products in a mixing, cooling or cooking container into which a medium is introduced, such as a liquid and/or inert gas.